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Biomedical subjects

B Marincek

Publications and source records attributed to B Marincek.

At least 19 recordsLinked to original sources
PubMed2006

[Influence of body mass index on coronary artery opacification in 64-slice CT angiography].

PURPOSE: To evaluate the influence of the body mass index (BMI) on coronary artery opacification in 64-slice CT. MATERIAL AND METHODS: Sixty-two patients retrospectively underwent ECG-gated 64-slice CT coronary angiography (tube potential 120 kV, tube current time product 650 mAs) after intravenous injection of 80 ml of iodinated contrast agent (320 mg/ml, 5 ml/s). Attenuation values (HU) were measured and contrast-to-noise ratios (CNR) were calculated in the right coronary artery (RCA) and left main artery (LMA). The CNR was defined as the difference between the mean attenuation in the vessel and the mean attenuation in the perivascular fat tissue divided by the image noise in the ascending aorta. The height and weight of the patients at the time of the CT scan were recorded and the BMI was calculated. RESULTS: The mean BMI was 26.2 +/- 3.2 kg/m (2) (range 19.7 - 32.2 kg/m (2)), the mean attenuation in the LMA was 330 +/- 64 HU, and the mean attenuation in the RCA was 309 +/- 68 HU. The CNR in the LMA was 16.7 +/- 3.8, and the CNR in the RCA was 15.9 +/- 3.6. The image noise in the ascending aorta significantly correlated with the BMI (r = 0.36, p < 0.01). A weak negative correlation was found between the BMI and LMA attenuation (r = - 0.28, p < 0.05), whereas no significant correlation was found for the RCA (r = - 0.21, p = 0.12). A significant negative correlation was found between the BMI and the CNR in the RCA (r = - 0.41, p < 0.05) and the LMA (r = - 0.47, p < 0.001). CONCLUSION: With constant scan parameters and a constant contrast medium amount, the CNR in both coronary arteries decreases while the BMI increases. This implies a modification of previously standardized and fixed examinations with respect to individually adapted protocols with variable parameters for CT coronary angiography.

Adult↗
PubMed2006

[Non-invasive assessment of the perfusion of wounds using power Doppler imaging: vacuum assisted closure versus direct wound closure].

AIM: The goal of our study was to assess the perfusion in wounds treated by vacuum assisted closure (VAC) compared to primary wound closure. METHOD: Power Doppler Ultrasound (PDUS) was carried out under standardised conditions in 15 VAC-treated and 10 primarily closed wounds as well as on altogether 25 intraindividual reference areas. All data were sent to a work station for post-processing to determine the perfused area. Statistical data analysis was performed with the Mann-Whitney test. RESULTS: Both VAC-treated wounds and primarily closed wounds showed a significant increase of the perfusion when compared to the intraindividual reference area (p < 0.0001). In VAC-treated wounds, a markedly increased perfusion was measured compared to the wounds closed primarily (p < 0.0001). Perfusion decreased during treatment, but in two VAC-treated wounds, an initial increase of the perfusion was observed. Both these wounds were grossly infected. CONCLUSION: PDUS allows the quantification of the differences in wound perfusion. This can be helpful in the detection of progressive local wound infections.

Female↗
PubMed2005

Coronal ultra-thick multiplanar CT reconstructions (MPR) of the pelvis in the multiple trauma patient: an alternative for the initial conventional radiograph.

PURPOSE: Multiple trauma patients with clinically suspected pelvic fractures often directly undergo a CT scan. However, the initial portable pelvis film (PPF) for further follow-up is then not available. This study examines whether coronal ultra-thick multiplanar reconstructions from CT data are similar when compared with the initial PPF, thus having the potential to serve as an alternative baseline image. MATERIALS AND METHODS: Initial PPF and coronal ultra-thick multiplanar CT reconstructions of 33 multiple trauma patients with pelvic fractures were retrospectively analyzed by two independent radiologists with regard to image quality, visualization of anatomical landmarks, and diagnostic accuracy. The primary diagnosis of pelvic fractures was made by using thin axial CT images and thin slice coronal and sagittal reconstructions and served as the standard of reference. RESULTS: Coronal ultra-thick multiplanar CT reconstructions were superior to PPF regarding image adjustment (p < 0.02), absence of overlaying structures (p < 0.05), and overall image quality (p < 0.01). Visualization of most anatomical landmarks was similar with both modalities, except of the iliosacral joint and acetabular lines which were more accurately depicted on ultra-thick multiplanar CT reconstructions (p < 0.05). Diagnostic accuracy of coronal ultra-thick CT reconstructions was similar to PPF regarding most fracture types, except of a higher accuracy of coronal ultra-thick CT reconstructions for iliosacral joint and acetabular column fractures (p < 0.05). CONCLUSION: Coronal ultra-thick multiplanar CT reconstructions of the pelvis provide similar image quality and diagnostic accuracy compared to PPF and are therefore suited as alternative baseline image in multiple trauma patients who directly undergo CT.

Adult↗
PubMed2005

[Diagnostic assessment of painless microhematuria: prospective study comparing image quality, assessibility and diagnostic certainty of multidetector-row CT and intravenous pyelography within a single examination].

PURPOSE: The purpose of this study is to prospectively compare intravenous pyelography (IVP) and combined unenhanced and excretory phase multidetector-row CT (MDCT) with respect to image quality, diagnostic certainty and diagnostic concordance with the final clinical diagnosis in patients with painless microhematuria. MATERIALS AND METHODS: Unenhanced MDCT, IVP and excretory phase MDCT were performed in 59 consecutive patients (21 women, 38 men, mean age 56 +/- 19 years, range 23 - 83 years) with painless microhematuria of unknown origin during a single examination with a single contrast media application (100 ml, non-ionic iodinated contrast media). Images were assessed by two experienced urogenital radiologists in consensus for image quality, diagnostic certainty of stone detection, obstruction, parenchymal lesions and morphological distinctive features. Imaging diagnoses of MDCT and IVP were compared with the final clinical diagnoses. In case of failure to detect an relevant pathology, the final clinical diagnosis was established after a mean follow-up period of 18 +/- 6 months (10 months to 2 years). Costs and radiation exposure of IVP and MDCT were compared. RESULTS: MDCT scan performed better than IVP in terms of image quality for all regarded variables. Image quality of MDCT was rated in all parameters as very good or good; the image quality of IVP differed in a wide range. MDCT and IVP reached a sensitivity of 100 % and 50 % for stone detection (n = 14, p = 0.008), respectively. Two bladder stones were not detected by IVU but correctly seen with MDCT. MDCT and IVP were unsatisfactory for detecting transitional cell carcinomas (n = 4, 2 of 4 detected with MDCT, 0 of 4 detected with IVU). One false positive transitional cell carcinoma was detected with IVP, none with MDCT. Additional relevant pathological changes (one teratoma, one abdominal aortic aneurysma and one abscess) were detected using MDCT but missed with IVP. In 38 of 59 patients (64 %) imaging and clinical follow-up over up to 24 months did not reveal any pathology to explain the microhematuria. The costs of the IVP (283 Euro) were lower compared with non-enhanced MDCT (380 Euro) or combined non-enhanced and contrast-enhanced MDCT (560 Euro). The radiation exposure was 23 - 27 mSv for MDCT and 2.3 mSv for IVP. CONCLUSION: MDCT performed better regarding image quality, subjective diagnostic certainty and diagnostic results with respect to stone detection. Since urolithiasis is a frequent cause of painless microhematuria MDCT is recommended as the initial imaging modality rather than IVU.

Adult↗
PubMed2004

[Recurrent pneumonia--case report and review of the literature].

We report the case of a 70-year old man with recurrent pneumonia due to aspiration from an otherwise asymptomatic small oesophageal diverticula in the mid-oesophageal region. The diagnosis was finally established by videofluoroscopy of the oesophagus after repeated bronchoscopies and CT scans in the proceeding months. After thoracoscopic removal of the diverticula the patient remained free of disease. Oesophageal diverticula as a rare cause of repeated pneumonias should be kept in mind, even though there are no symptoms of gastro-oesophageal disease.

Aged↗
PubMed2004

Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

PURPOSE: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. MATERIALS AND METHODS: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of - 400 msec in all patients. In 10 patients additional reconstructions at - 200 msec, - 300 msec, and - 500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. RESULTS: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P < 0.05). The summary scores for visualization of bronchial segments for different diastolic reconstructions did not differ significantly. The effective radiation dose and the SNR were significantly higher with the ECG-gated acquisition technique (P < 0.05). CONCLUSION: The bronchial tree is significantly better visualized when using non-ECG-gated MDCT compared to ECG-gated MDCT. Additionally, non-ECG-gated techniques require less radiation exposure. Thus, the current retrospective ECG-gating technique does not provide any additional benefit for 3D visualization of the bronchial tree and VB.

Adult↗
PubMed2004

Time-effectiveness, observer-dependence, and accuracy of measurements of left ventricular ejection fraction using 4-channel MDCT.

PURPOSE: To evaluate the time-effectiveness, inter-observer variance, and accuracy of left ventricular ejection fraction (EF) measurements using retrospectively ECG-gated four-channel multi-detector row CT (MDCT) angiography in comparison with biplane cine-ventriculography. MATERIALS AND METHODS: Twenty consecutive patients underwent retrospectively ECG-gated MDCT angiography and conventional coronary angiography with biplane ventriculography. Raw MDCT data were reconstructed at 0 % - 90 % of the cardiac cycle in increments of 10 %. Ten geometrically identical multiplanar reformations parallel to the short axis of the heart were reconstructed in each patient. Three blinded readers segmented the left ventricle in the end-systolic and end-diastolic phase using standardized window settings in order to determine the EF. The EF was measured with biplane cine-ventriculography by two blinded readers and was compared with MDCT. The time needed for post-processing was recorded and the inter-observer agreement for both imaging techniques was assessed. RESULTS: Mean post-processing time was 63 +/- 3 min per patient for MDCT and 5.5 +/- 1.2 min for ventriculography. MDCT and ventriculography showed a good correlation (r = 0.83, p < 0.0001) for measurement of the EF. Mean errors of EF measurements for the three MDCT readers compared with the mean of the ventriculography were - 6.3 +/- 6.6 %, - 4.7 +/- 7.1 % and - 4.6 +/- 5.7 %, respectively. The mean differences between the three readers assessing MDCT were - 1.6 +/- 3.2 % (reader 1 versus 2, r = 0.96), - 1.6 +/- 5.6 % (1 versus 3, r = 0.95) and - 0.011 +/- 2.9 % (2 versus 3, r = 0.97, p < 0.0001). The mean differences between the two readers assessing ventriculography was 0.32 +/- 5.1 % (r = 0.88, p < 0.0001). CONCLUSIONS: MDCT correlates well with biplane cine-ventriculography but has the tendency to underestimate the left ventricular EF. Measurements using MDCT have a high inter-observer agreement, however, the time needed for additional MDCT data post-processing is still unacceptably long.

Aged↗
PubMed2004

Multi-detector row CT: effect of iodine dose reduction on hepatic and vascular enhancement.

PURPOSE: To evaluate the impact of different iodine concentrations of intravenous contrast agent on hepatic and vascular enhancement during arterial and porto-venous phase imaging using a 4-channel multi-detector row CT (MDCT). MATERIAL AND METHODS: One hundred consecutive patients referred for triphasic abdominal MDCT were randomly assigned into four groups receiving different iodine concentration (200, 250, 300 or 350 mg/ml). Non-contrast, arterial, and porto-venous phase 4-channel MDCT imaging was performed (VolumeZoom, Siemens, Germany). A fixed volume of 150 ml intravenous contrast agent at a rate of 3 ml/s was injected using an automatic bolus-tracking system (Care Bolus, Siemens, Erlangen). Hepatic and vascular enhancement values were measured over time and non-contrast values were subtracted in order to compute arterial and porto-venous mean hepatic (MHE) and mean aortic (MAE) enhancement for each group. Mean change of enhancement > 80 HU for the aorta and > 40 HU for the liver during porto-venous phase imaging was considered as sufficient enhancement. RESULTS: All groups achieved sufficient vascular enhancement during arterial phase imaging; MAE with 350 mg/ml (222 HU) and 300 mg/ml (213HU) was significantly better than with 250 mg (196HU) and 200 mg/ml (169 HU), whereas MHE showed no statistically significant difference between the groups (range 16 - 25 HU). Porto-venous MHE showed increased enhancement with larger concentrations, with significant differences among the groups. Only the higher concentration groups (350 mg/ml und 300 mg/ml) fulfilled in every individual the guidelines for sufficient porto-venous MHE. In the lower concentration groups, 8 patients with 200 mg/ml and 3 patients with 250 mg/ml showed enhancement values below the required minimum. CONCLUSION: A decrease in iodine contrast agent down to 200 mg/ml concentration is only tenable for propose of vascular aortic and hepatic arterial enhancement, whereas hepatic porto-venous phase imaging still requires concentrations at or above the level of 300 mg/ml.

Adult↗
PubMed2004

[Application of multislice spiral CT (MSCT) in multiple injured patients and its effect on diagnostic and therapeutic algorithms].

The initial diagnostic work-up of trauma victims with multiple injuries is currently a combination of conventional radiography (CR), ultrasound (US), and computed tomography (CT). This article reviews the diagnostic quality of the different imaging modalities regarding detection and classification of injuries. CT performs better than US in detecting traumatic lesions of abdominal parenchymal organs. Furthermore, CT is better than CR in detecting therapeutically relevant chest and bone injuries. MSCT may replace CR and US under the condition that it is faster than or at least as fast as the conventional approach to diagnose life threatening injuries. This can be achieved only by changing the work-flow for the entire trauma team including radiologist. Furthermore, certain prerequisites must be fulfilled including integration of a MSCT scanner into the emergency room. An optimized whole body CT protocol for the assessment of trauma victims using MSCT as well as a two-step algorithm for reporting the imaging findings depending on their clinical significance is presented.

Abdominal Injuries↗
PubMed2003

[Contrast-enhanced MR angiography for differentiation between perigastric and submucosal gastric fundal varices].

PURPOSE: To evaluate contrast-enhanced MR angiography for the distinction between perigastric and submucosal fundal varices. MATERIALS AND METHODS: Nineteen consecutive patients with clinically suspected fundal varices underwent contrast-enhanced MR angiography and endoscopic ultrasound (EUS) within one week. Diagnostic confidence for the detection of perigastric and submucosal fundal varices was compared between MR angiography (two radiologists) and EUS (one gastroenterologist), and the agreement of size and location was evaluated. RESULTS: Both MR angiography and EUS detected perigastric varices in all 19 patients and submucosal fundal varices in 14 of the 19 patients. The interobserver reliability of MR angiography was good for measuring the variceal diameter (kappa = 0.76) and excellent for localizing the varices (kappa = 1.0). EUS and MR angiography agreed in 12 of 14 patients (86 %) in determining variceal diameter and location. CONCLUSIONS: Contrast-enhanced MR angiography is comparable to endoscopic ultrasound in the detection and characterization of gastric fundal varices.

Adult↗
PubMed2003

Angiosarcoma of the pulmonary trunk mimicking pulmonary thromboembolic disease. A case report.

We report on a 59-year-old male patient who suffered from dyspnea, cough and hemoptysis. Initial chest X-ray revealed a prominent right pulmonary artery (RPA) and MR imaging showed a "filling defect" within the main pulmonary trunk and RPA indicating pulmonary thromboembolic disease. Despite systemic anticoagulation, symptoms progressed. Follow-up CT showed an enlarging "filling defect" with additional extension into the left pulmonary artery as well as multiple intrapulmonary nodules. Lesion biopsy revealed a pulmonary artery angiosarcoma. Imaging findings are presented. Our case illustrates that pulmonary artery angiosarcoma should be included in the differential diagnosis of pulmonary thromboembolic disease in cases where a) symptoms do not respond to anticoagulation, b) no source of thrombi/emboli can be detected and c) pulmonary nodules/metastases develop on follow-up.

Diagnosis, Differential↗
PubMed2003

Detection of submucosal gastric fundal varices with multi-detector row CT angiography.

BACKGROUND AND AIM: The diagnosis of submucosal fundal varices is challenging. Currently, endoscopy and endoscopic ultrasound (EUS) are considered most useful for this purpose. The aim of this study was to evaluate if multi-detector row CT (MDCT) angiography contributes to the diagnosis of submucosal fundal varices. PATIENTS AND METHODS: Twenty two patients with endoscopically suspected fundal varices were prospectively included in the study. All patients underwent EUS and MDCT angiography. Levels of agreement between EUS and MDCT angiography for the detection of submucosal and perigastric fundal varices were evaluated by three blinded independent readers. In addition, variceal size and location, as well as afferent and efferent vessels of the submucosal varices, were determined. RESULTS: Good or excellent image quality of MDCT angiography was obtained in 21/22 patients (95%). Based on EUS, submucosal varices were detected in 16 of 22 patients (73%) and perigastric varices in 22/22 patients (100%). Using MDCT angiography, the presence of submucosal varices was confirmed in all of these 16 patients by all three readers. Perigastric varices were also confirmed in all 22 patients by all three readers. In addition, all three readers noted the presence of a submucosal varix in an additional patient which was not detected on initial EUS. MDCT angiography showed an excellent interobserver reliability with regard to variceal diameter (kappa=0.90) and variceal location (kappa=0.94). Based on MDCT angiography, afferent and efferent vessels of submucosal varices included the left gastric vein in 11 (65%), the posterior/short gastric veins in 15 (88%), gastrorenal shunts in 10 (59%), the left inferior phrenic vein in six (35%), and the left pericardiophrenic vein in six (35%) of 17 patients. CONCLUSIONS: MDCT angiography is equivalent to EUS in terms of detection and characterisation of fundal varices, in particular with regard to the distinction between submucosal and perigastric fundal varices.

Adult↗
PubMed2002

Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies.

Common causes of acute abdominal pain include appendicitis, cholecystitis, bowel obstruction, urinary colic, perforated peptic ulcer, pancreatitis, diverticulitis, and nonspecific, nonsurgical abdominal pain. The topographic classification of acute abdominal pain (pain in one of the four abdominal quadrants, diffuse abdominal pain, flank or epigastric pain) facilitates the choice of the imaging technique. The initial radiological evaluation often consists of plain abdominal radiography, despite significant diagnostic limitations. The traditional indications for plain films--bowel obstruction, pneumoperitoneum, and the search of ureteral calculi--are questioned by helical computed tomography (CT). Although ultrasonography (US) is in many centers the modality of choice for imaging the gallbladder and the pelvis in children and women of reproductive age, CT is considered to be one of the most valued tools for triaging patients with acute abdominal pain. CT is particularly beneficial in patients with marked obesity, unclear US findings, bowel obstruction, and multiple lesions. The introduction of multidetector row CT (MDCT) has further enhanced the utility of CT in imaging patients with acute abdominal pain.

Abdominal Pain↗
PubMed2002

[Differential diagnosis of benign and malignant mammary lesions with special regard to the BI-RADS((R)) classification system in mammography].

Mammography is the imaging method of choice for the diagnostic workup of breast tumors in screening programs as well as in symptomatic patients. Quality assurance is one of the main prerequisites for a successful performance in both fields. Quality assurance on the technical and film processing level can be easily achieved compared to reporting and outcome monitoring on the level of the physician performing mammography. This is especially due to the lack of standards of the written reports. This article reviews the Breast Imaging Reporting and Data System (BI-RADS((R))) developed and commercialized by the American College of Radiology, contains several examples of lesion classification and discusses the significance of the BI-RADS((R)) approach.

Breast↗